1. Technical Field
Eco-friendly, or “green,” compositions that include “green” surfactants, “green” linkers, natural fragrances, natural insecticides, and other natural organic actives such as natural oils are disclosed. The composition may be used as a natural cleaning product with performance comparable to conventional cleaning products with less desirable ecological profiles. The composition may also be used to deliver organic actives over a long period of time.
2. Description of the Related Art
In recent years, there has been a significant amount of global consumer awareness in “green”, i.e., eco-friendly, household or personal care products. As a result, increasing efforts have been directed to the development of household products with desirable ecological profiles. For example, products containing ingredients that are derived from natural and renewable sources, as well as products that are biodegradable in natural environments, have been a focus of this global “eco-friendly” trend.
Indeed, products derived from renewable resources, such as plants, contribute less greenhouse gas because of their closed CO2 cycle. Specifically, during growth, plants consume the same amount of carbon dioxide (CO2) and water (H2O) as they subsequently release into the atmosphere by biodegradation after use. Therefore, products derived from renewable resources, such as plants, are considered to be “green” and having zero or reduced “carbon footprint” when compared with petrochemical-based products. Common ingredients in household products such as surfactants, fragrances, oils and solvents can be derived directly or indirectly from both renewable sources such as plant materials or non-renewable sources such as petroleum.
The basic way in which surfactants act is determined by their structure. With a hydrophilic head and hydrophobic tail, surfactant molecules become interposed between water and water-insoluble substances such as oil, dirt and grease, collectively referred to as “soil particles.” By enriching themselves at the boundaries which water forms with air or oil, surfactants lower the surface tension of the water. When dissolved in water at higher concentrations, surfactant molecules group themselves together to form spherical structures around soil particles referred to as micelles. The inwardly directed hydrophobic groups surround soil particles and keep the otherwise insoluble soil particles in solution. Surfactants are generally classified as being anionic, cationic, non-ionic or amphoteric surfactants depending on the type and charge of the hydrophilic groups.
While most surfactants are still derived from petroleum chemicals, surfactants derived from plant-based carbohydrates and oils are becoming available. One suitable renewable raw material for surfactant production is glucose, which is reacted with alcohol to produce alkyl polyglycosides (also known as alkyl polyglucosides). Alkyl polyglycosides have been used in cosmetics products, agricultural formulations and as surfactants in industrial cleaning agents. Alkyl polyglycosides include a hydrophobic (or lipophilic) hydrocarbon chain is formed by a fatty alcohol (e.g., dodecanol, tetradecanol) obtained from a saturated tropical oils such as palm or coconut oil. The hydrophilic part of the molecule, derived from glucose or dextrose, maybe obtained from starch, most commonly from corn.
In addition to its desirable ecological profile, alkyl polyglycosides have good compatibility with the eyes, skin and mucous membranes and even reduce the irritant effects of surfactant combinations. Alkyl polyglycosides are also completely biodegradable, both aerobically and anaerobically.
Some anionic surfactants may also have immediate precursors that are obtainable from natural and renewable sources. For example, long-chain alkyl sulfates may be conveniently prepared from fatty alcohols derived from coconut oils. In particular, sodium coco sulfate (SCS) is derived from pure coconut oil and includes a mixture of sodium alkyl sulfate with the main component being sodium lauryl sulfate. Sodium coco sulfate may be used in a wide variety of consumer products in which viscosity building and foam characteristics are of importance. It can be incorporated into shampoos, hand soaps, bath products, shaving creams and medicated ointments.
In formulating micro- or nano-emulsion, linkers may be used to facilitate the interactions among water phase, oil phase, and surfactant(s). Specifically, lipophilic linkers may enhance the surfactant-soil interaction whereas hydrophilic linkers may enhance the surfactant-water interaction. Like surfactants, “green” linkers derived from natural and renewable sources are becoming available, although traditionally they are derived from petroleum chemicals.
Compositions for controlled release of active substances are also known in the art. For example, fragrance or insecticide compositions in the form of single-phase solution have been developed to allow prolonged release of a fragrance or insecticide into the air. However, those compositions generally have a less desirable ecological profile in order to maintain their fragrance or insecticide delivery performance.
Thus, there is a need for improved household products derived from natural, renewable sources such as plants or that have a higher percentage of components that are derived from natural, renewable sources. Moreover, there is a need for a cleaning product with an improved ecological profile and performance that is comparable, or even superior, to conventional cleaning products with less desirable ecological profiles. Finally, there is a need for a “green” composition that allows a controlled release of a natural organic active such as a fragrance or insecticide.